/*
 * Copyright (c) 2009, Hamish Morgan. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * 3. Neither the name of the University of Sussex nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
package locusts.server.admin;

import java.util.ArrayList;
import java.util.List;
import javax.swing.ComboBoxModel;
import javax.swing.event.EventListenerList;
import javax.swing.event.ListDataEvent;
import javax.swing.event.ListDataListener;
import locusts.common.entities.Entity;
import locusts.common.entities.EntityList;
import locusts.common.entities.EntityType;

/**
 * A  combo box model for handling the "type" property of an entity. It
 * allows the user to select a type from a list, rather than type in the id.
 *
 * @author Hamish Morgan
 */
public class EntityComboBoxModel implements ComboBoxModel {

    private final EntityList allEntities;
    private final EntityType type;
    private List<Entity> entities;
    private Entity selected;

    public EntityComboBoxModel(EntityList allEntities, EntityType type) {
        this.allEntities = allEntities;
        this.allEntities.addListDataListener(new ListDataHandler());
        this.type = type;
        entities = new ArrayList<Entity>();
        updateEntities();
    }

    private void updateEntities() {
        List<Entity> newEntities = allEntities.getAllByType(type);
        newEntities.add(null);
        boolean changed = newEntities.equals(entities);
        entities = newEntities;

        if (changed) {
            if (selected != null && !entities.contains(selected))
                selected = null;
            if (selected == null && !entities.isEmpty())
                selected = entities.get(0);
            fireContentsChanged(0, entities.size() - 1);
        }
    }

    private class ListDataHandler implements ListDataListener {

        public void intervalAdded(ListDataEvent e) {
            updateEntities();
        }

        public void intervalRemoved(ListDataEvent e) {
            updateEntities();
        }

        public void contentsChanged(ListDataEvent e) {
            updateEntities();
        }
    }

    public void setSelectedItem(Object o) {
        if (o instanceof Entity && entities.contains((Entity) o))
            selected = (Entity) o;
        else {
            selected = null;
        }

    }

    public Object getSelectedItem() {
        return selected;
    }

    public int getSize() {
        return entities.size();
    }

    public Object getElementAt(
            int i) {
        return entities.get(i);
    }
// ==============================================
// List model stuff
//
    private final transient EventListenerList listeners =
            new EventListenerList();

    protected void fireIntervalAdded(int index0, int index1) {
        final ListDataEvent e = new ListDataEvent(
                this, ListDataEvent.INTERVAL_ADDED, index0, index1);
        for (ListDataListener l : listeners.getListeners(
                ListDataListener.class))
            l.intervalAdded(e);
    }

    protected void fireIntervalRemoved(int index0, int index1) {
        final ListDataEvent e = new ListDataEvent(this,
                ListDataEvent.INTERVAL_REMOVED, index0, index1);
        for (ListDataListener l : listeners.getListeners(
                ListDataListener.class))
            l.intervalRemoved(e);
    }

    protected void fireContentsChanged(int index0, int index1) {
        final ListDataEvent e = new ListDataEvent(this,
                ListDataEvent.CONTENTS_CHANGED, index0, index1);
        for (ListDataListener l : listeners.getListeners(
                ListDataListener.class))
            l.contentsChanged(e);
    }

    public void addListDataListener(ListDataListener listener) {
        listeners.add(ListDataListener.class, listener);
    }

    public void removeListDataListener(ListDataListener listener) {
        listeners.remove(ListDataListener.class, listener);
    }
}
